Re: [PATCH v5 3/3] clk: qcom: Add IPQ8074 APSS clock controller

From: Konrad Dybcio
Date: Wed Jul 06 2022 - 09:21:23 EST




On 5.07.2022 21:10, Robert Marko wrote:
> IPQ8074 APSS clock controller provides the clock for the IPQ8074 CPU
> cores, thus also providing support for CPU frequency scaling.
>
> It looks like they are clocked by the XO and a custom APSS type PLL.
>
> Co-developed-by: Christian Marangi <ansuelsmth@xxxxxxxxx>
> Signed-off-by: Christian Marangi <ansuelsmth@xxxxxxxxx>
> Signed-off-by: Robert Marko <robimarko@xxxxxxxxx>
> ---
> Changes in v5:
> * Drop F define as its already defined in clk-rgc.h
> * Correct the driver name to not include commas
> * Correct Christian-s SoB
> * Add MODULE_ALIAS so it gets loaded if built as a module
>
> Changes in v2:
> * Convert to using parent-data instead of parent-names
> ---
> drivers/clk/qcom/Kconfig | 11 +++
> drivers/clk/qcom/Makefile | 1 +
> drivers/clk/qcom/apss-ipq8074.c | 169 ++++++++++++++++++++++++++++++++
> 3 files changed, 181 insertions(+)
> create mode 100644 drivers/clk/qcom/apss-ipq8074.c
>
> diff --git a/drivers/clk/qcom/Kconfig b/drivers/clk/qcom/Kconfig
> index fc45d00eec42..a3ba541a9dee 100644
> --- a/drivers/clk/qcom/Kconfig
> +++ b/drivers/clk/qcom/Kconfig
> @@ -134,6 +134,17 @@ config IPQ_APSS_6018
> Say Y if you want to support CPU frequency scaling on
> ipq based devices.
>
> +config IPQ_APSS_8074
> + tristate "IPQ8074 APSS Clock Controller"
> + select IPQ_GCC_8074
> + depends on QCOM_APCS_IPC || COMPILE_TEST
> + help
> + Support for APSS clock controller on IPQ8074 platforms. The
> + APSS clock controller manages the Mux and enable block that feeds the
> + CPUs.
> + Say Y if you want to support CPU frequency scaling on
> + IPQ8074 based devices.
> +
> config IPQ_GCC_4019
> tristate "IPQ4019 Global Clock Controller"
> help
> diff --git a/drivers/clk/qcom/Makefile b/drivers/clk/qcom/Makefile
> index 08594230c1c1..226f3b5cefde 100644
> --- a/drivers/clk/qcom/Makefile
> +++ b/drivers/clk/qcom/Makefile
> @@ -23,6 +23,7 @@ obj-$(CONFIG_APQ_MMCC_8084) += mmcc-apq8084.o
> obj-$(CONFIG_CLK_GFM_LPASS_SM8250) += lpass-gfm-sm8250.o
> obj-$(CONFIG_IPQ_APSS_PLL) += apss-ipq-pll.o
> obj-$(CONFIG_IPQ_APSS_6018) += apss-ipq6018.o
> +obj-$(CONFIG_IPQ_APSS_8074) += apss-ipq8074.o
> obj-$(CONFIG_IPQ_GCC_4019) += gcc-ipq4019.o
> obj-$(CONFIG_IPQ_GCC_6018) += gcc-ipq6018.o
> obj-$(CONFIG_IPQ_GCC_806X) += gcc-ipq806x.o
> diff --git a/drivers/clk/qcom/apss-ipq8074.c b/drivers/clk/qcom/apss-ipq8074.c
> new file mode 100644
> index 000000000000..36fafa71c4ea
> --- /dev/null
> +++ b/drivers/clk/qcom/apss-ipq8074.c
> @@ -0,0 +1,169 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2022, The Linux Foundation. All rights reserved.
> + */
> +
> +#include <linux/clk-provider.h>
> +#include <linux/err.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +
> +#include <dt-bindings/clock/qcom,apss-ipq8074.h>
> +
> +#include "common.h"
> +#include "clk-regmap.h"
> +#include "clk-pll.h"
> +#include "clk-rcg.h"
> +#include "clk-branch.h"
> +#include "clk-alpha-pll.h"
> +#include "clk-regmap-divider.h"
> +#include "clk-regmap-mux.h"
> +
> +enum {
> + P_XO,
> + P_GPLL0,
> + P_GPLL2,
> + P_GPLL4,
> + P_APSS_PLL_EARLY,
> + P_APSS_PLL
> +};
> +
> +static struct clk_alpha_pll apss_pll_early = {
> + .offset = 0x5000,
> + .regs = clk_alpha_pll_regs[CLK_ALPHA_PLL_TYPE_APSS],
> + .clkr = {
> + .enable_reg = 0x5000,
> + .enable_mask = BIT(0),
> + .hw.init = &(struct clk_init_data){
> + .name = "apss_pll_early",
> + .parent_data = &(const struct clk_parent_data) {
> + .fw_name = "xo", .name = "xo"
Since you're only adding this driver now, no DT uses it an you
should drop the .name lookup.


> + },
> + .num_parents = 1,
> + .ops = &clk_alpha_pll_huayra_ops,
> + },
> + },
> +};
> +
> +static struct clk_alpha_pll_postdiv apss_pll = {
> + .offset = 0x5000,
> + .regs = clk_alpha_pll_regs[CLK_ALPHA_PLL_TYPE_APSS],
> + .width = 2,
> + .clkr.hw.init = &(struct clk_init_data){
> + .name = "apss_pll",
> + .parent_hws = (const struct clk_hw *[]){
> + &apss_pll_early.clkr.hw },
> + .num_parents = 1,
> + .ops = &clk_alpha_pll_postdiv_ro_ops,
> + },
> +};
> +
> +static const struct clk_parent_data parents_apcs_alias0_clk_src[] = {
> + { .fw_name = "xo", .name = "xo" },
> + { .fw_name = "gpll0", .name = "gpll0" },
> + { .fw_name = "gpll2", .name = "gpll2" },
> + { .fw_name = "gpll4", .name = "gpll4" },
> + { .hw = &apss_pll.clkr.hw },
> + { .hw = &apss_pll_early.clkr.hw },
> +};
> +
> +static const struct parent_map parents_apcs_alias0_clk_src_map[] = {
> + { P_XO, 0 },
> + { P_GPLL0, 4 },
> + { P_GPLL2, 2 },
> + { P_GPLL4, 1 },
> + { P_APSS_PLL, 3 },
> + { P_APSS_PLL_EARLY, 5 },
Looks like it only supports frequencies with APSS_PLL_EARLY and XO
as parents? Are all of these other PLLs necessary here?

> +};
> +
> +struct freq_tbl ftbl_apcs_alias0_clk_src[] = {
> + F(19200000, P_XO, 1, 0, 0),
> + F(403200000, P_APSS_PLL_EARLY, 1, 0, 0),
> + F(806400000, P_APSS_PLL_EARLY, 1, 0, 0),
> + F(1017600000, P_APSS_PLL_EARLY, 1, 0, 0),
> + F(1382400000, P_APSS_PLL_EARLY, 1, 0, 0),
> + F(1651200000, P_APSS_PLL_EARLY, 1, 0, 0),
> + F(1843200000, P_APSS_PLL_EARLY, 1, 0, 0),
> + F(1920000000, P_APSS_PLL_EARLY, 1, 0, 0),
> + F(2208000000UL, P_APSS_PLL_EARLY, 1, 0, 0),
Every frequency is a div1 and comes from a single clock..
is this correct? This sounds like a simple mux that only
switches between XO and APSS_PLL_EARLY..

> + { }
> +};
> +
> +struct clk_rcg2 apcs_alias0_clk_src = {
> + .cmd_rcgr = 0x0050,
> + .freq_tbl = ftbl_apcs_alias0_clk_src,
> + .hid_width = 5,
> + .parent_map = parents_apcs_alias0_clk_src_map,
> + .clkr.hw.init = &(struct clk_init_data){
> + .name = "apcs_alias0_clk_src",
> + .parent_data = parents_apcs_alias0_clk_src,
> + .num_parents = ARRAY_SIZE(parents_apcs_alias0_clk_src),
> + .ops = &clk_rcg2_ops,
> + .flags = CLK_SET_RATE_PARENT,
> + },
> +};
> +
> +static struct clk_branch apcs_alias0_core_clk = {
> + .halt_reg = 0x0058,
> + .halt_bit = 31,
> + .clkr = {
> + .enable_reg = 0x0058,
> + .enable_mask = BIT(0),
> + .hw.init = &(struct clk_init_data){
> + .name = "apcs_alias0_core_clk",
> + .parent_hws = (const struct clk_hw *[]){
> + &apcs_alias0_clk_src.clkr.hw },
> + .num_parents = 1,
> + .flags = CLK_SET_RATE_PARENT |
> + CLK_IS_CRITICAL,
This can fit in a single line.

> + .ops = &clk_branch2_ops,
> + },
> + },
> +};
> +
> +static struct clk_regmap *apss_ipq8074_clks[] = {
> + [APSS_PLL_EARLY] = &apss_pll_early.clkr,
> + [APSS_PLL] = &apss_pll.clkr,
> + [APCS_ALIAS0_CLK_SRC] = &apcs_alias0_clk_src.clkr,
> + [APCS_ALIAS0_CORE_CLK] = &apcs_alias0_core_clk.clkr,
> +};
> +
> +static const struct regmap_config apss_ipq8074_regmap_config = {
> + .reg_bits = 32,
> + .reg_stride = 4,
> + .val_bits = 32,
> + .max_register = 0x5ffc,
> + .fast_io = true,
> +};
> +
> +static const struct qcom_cc_desc apss_ipq8074_desc = {
> + .config = &apss_ipq8074_regmap_config,
> + .clks = apss_ipq8074_clks,
> + .num_clks = ARRAY_SIZE(apss_ipq8074_clks),
> +};
> +
> +static int apss_ipq8074_probe(struct platform_device *pdev)
> +{
> + struct regmap *regmap;
> +
> + regmap = dev_get_regmap(pdev->dev.parent, NULL);
> + if (!regmap)
> + return -ENODEV;
> +
> + return qcom_cc_really_probe(pdev, &apss_ipq8074_desc, regmap);
qcom_cc_probe?

> +}
> +
> +static struct platform_driver apss_ipq8074_driver = {
> + .probe = apss_ipq8074_probe,
> + .driver = {
> + .name = "qcom-apss-ipq8074-clk",
> + },
> +};
> +
> +module_platform_driver(apss_ipq8074_driver);
> +
> +MODULE_ALIAS("platform:qcom-apss-ipq8074-clk");
> +MODULE_DESCRIPTION("Qualcomm IPQ8074 APSS clock driver");
> +MODULE_LICENSE("GPL");
"GPL v2"?

Konrad